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With enhanced recovery after surgery (ERAS), research and application of knee revision protheses and customized components or prostheses in the past decade, revision of total knee arthroplasty (TKA) is developing rapidly. However, periprosthetic joint infection (PJI) has always been a major clinical challenge. A comprehensive preoperative examination to find any potential infection sites should be conducted. The overall condition of the patients should be improved. Surgeons should evaluate the classification and degree of soft tissue and bone defects comprehensively and carefully select appropriate surgical approaches, bone reconstruction strategies, and revision prostheses to ultimately restore the alignment, stability, and the range of motion of the knee joint. In the future, efforts should be made to build a team of experts for the support of revisions of TKAs, including preoperative planning, 3D printing, surgical techniques, and ERAS. Nevertheless, primary TKAs protocols should always be firmly sticked to, which are a key to a low rate of revision surgeries. Prevention of PJIs and periprosthetic fractures, as well as establishing a high-quality follow-up system are of the same importance.
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Objective:To analyze the clinical efficacy of internal fixation and prosthesis revision in the treatment of periprosthesis fracture after total knee arthroplasty.Methods:A total of 35 patients (35 knees) with periprosthetic fractures after total knee arthroplasty were retrospectively analyzed from January 2008 to January 2022 in the Department of Orthopaedics, West China Hospital, Sichuan University, including 13 males and 22 females, aged 71.4±4.1 years (range, 62-81 years). Left knee 19 cases, right knee 16 cases. There were 20 cases of Rorabeck type II and 15 cases of Rorabeck type III. The initial replacement was performed using a fixed platform post-stabilized knee prosthesis, which was fixed with bone cement. Patients with Rorabeck type II were treated with internal fixation alone (internal fixation group) and patients with Rorabeck type III underwent revision with replacement prosthesis (revision group). The Hospital for Special Surgery (HSS) score, range of motion (ROM) of knee joint, alignment of lower extremity and incidence of postoperative complications were compared between the two groups.Results:All patients successfully completed the operation and were followed up for 5.2±3.6 years (range, 1-12 years). Intraoperative blood loss was 680±102 ml (range, 420-1100 ml). The operative time in the internal fixation group was 105±17 min, which was less than 140±21 min in the revision group, and the difference was statistically significant ( t=-5.450, P<0.001). There was no complication of nerve or blood vessel injury during the operation. Five cases in the internal fixation group had unsatisfactory lower extremity force lines (>3° deviation from normal) after surgery, and all lower extremity force lines in the revision group were satisfied, and the difference in the satisfaction rate of lower extremity force lines between the two groups was not statistically significant ( P=0.057). The fracture healing time, knee ROM and HSS scores at the last follow-up were 5.1±1.3 months, 86°±5° and 84±5 in the internal fixation group and 4.8±1.5 months, 83°±6° and 82±4 in the revision group. One case in the revision group was diagnosed postoperatively with periprosthetic infection with pathogen culture suggestive of Candida albicans, recurrent anterior knee sinus tracts and patellar ectasia, which progressed to osteomyelitis, and mid-thigh amputation was performed 1 year after revision. Conclusion:The stability of prosthesis is an important reference for the treatment of periprosthetic fractures after total knee arthroplasty. Strong internal fixation in patients with unloosened prosthesis and revision with replacement of prosthesis in patients with loose prosthesis can achieve good knee joint function.
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Objective@#To investigate the influence of displacement of femoral and tibial components on the biomechanics of femoral or tibial bone in coronal view.@*Methods@#A series of CT and MRI of the left knee joint of a Han male volunteer was taken and a three-dimensional finite element model of the healthy knee joint was established. The femoral component and the tibial component were designed with varus 6°, varus 3°, 0°, valgus 3°, and valgus 6°, and were combined into 25 three-dimensional finite element model (FEM) of medial unicompartmental knee arthroplasty. A 1 000 N load was applied along the femoral mechanical axis. The von Mises cloud stress distribution was observed. Moreover, the lateral compartment load ratio, the high contact stress of cancellous bone and medial cortical bone below the tibial component, the upper surface of the polyethylene liner, and the femoral cartilage in the lateral compartment was measured. The statistically significant indicators compared with the neutral position (0° varus or valgus of the tibia and the femoral prosthesis, and 5° posterior slope of tibia prosthesis) were identified by scatter plots to find the dense and sparse areas of point items. The optimal position of the femoral component and the tibial component was determined by the number of items with statistical significance in the sparse area.@*Results@#When the femoral component was placed at 0° position, there was no significant difference in the high contact stress of cancellous bone below the tibial component in the five groups. When the femoral component was placed at 0° position, the tibial component was 6° varus or 6° valgus and the stress was increased by 9.21±3.38 MPa and 9.08±4.13 MPa (P<0.05), respectively. With the changes of femoral and tibial components from 6° varus to 6° valgus, the high contact stress of the medial cortical bone below the tibia was gradually decreased (P<0.05). When the femoral component was placed at 0°, the tibial component changes from 6° varus to 6° valgus without significant difference in the high contact stress on the upper surface of each group of polyethylene gasket. Compared with the neutral position group, the high contact stress of the 6° varus or 6° valgus group were increased by 2.88±2.53 MPa and 3.47±2.86 MPa, respective ly (P<0.05). The lateral compartment load ratio and the high contact stress of lateral compartment femoral cartilage was gradually decreased (P<0.05), when the femoral and tibial components changed from 6° varus to 6° valgus. The number (2.8%, 1/36) of indicators in the sparse area (the combination of all combinations of femur or tibia from 3° varus to 3° valgus) was less than that (57.8%, 37/64) in the dense area (set of all combinations except sparse area), and the difference was significant (χ2=29.61, P<0.001).@*Conclusion@#It is suggested that the position of the femoral component and the tibial component in fixed medial unicompartmental arthroplasty should not exceed 3° varus or valgus in patients with standard lower limb alignment.
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Objective To investigate the influence of displacement of femoral and tibial components on the biomechanics of femoral or tibial bone in coronal view.Methods A series of CT and MRI of the left knee joint of a Han male volunteer was taken and a three-dimensional finite element model of the healthy knee joint was established.The femoral component and the tibial component were designed with varus 6°,varus 3°,0°,valgus 3°,and valgus 6°,and were combined into 25 three-dimensional finite element model (FEM) of medial unicompartmental knee arthroplasty.A 1 000 N load was applied along the femoral mechanical axis.The von Mises cloud stress distribution was observed.Moreover,the lateral compartment load ratio,the high contact stress of cancellous bone and medial cortical bone below the tibial component,the upper surface of the polyethylene liner,and the femoral cartilage in the lateral compartment was measured.The statistically significant indicators compared with the neutral position (0° varus or valgus of the tibia and the femoral prosthesis,and 5° posterior slope of tibia prosthesis) were identified by scatter plots to find the dense and sparse areas of point items.The optimal position of the femoral component and the tibial component was determined by the number of items with statistical significance in the sparse area.Results When the femoral component was placed at 0° position,there was no significant difference in the high contact stress of cancellous bone below the tibial component in the five groups.When the femoral component was placed at 0° position,the tibial component was 6° varus or 6° valgus and the stress was increased by 9.21±3.38 MPa and 9.08±4.13 MPa (P<0.05),respectively.With the changes of femoral and tibial components from 6° varus to 6° valgus,the high contact stress of the medial cortical bone below the tibia was gradually decreased (P< 0.05).When the femoral component was placed at 0°,the tibial component changes from 6° varus to 6° valgus without significant difference in the high contact stress on the upper surface of each group of polyethylene gasket.Compared with the neutral position group,the high contact stress of the 6° varus or 6° valgus group were increased by 2.88±2.53 MPa and 3.47±2.86 MPa,respectively (P<0.05).The lateral compartment load ratio and the high contact stress of lateral compartment femoral cartilage was gradually decreased (P<0.05),when the femoral and tibial components changed from 6° varus to 6° valgus.The number (2.8%,1/36) of indicators in the sparse area (the combination of all combinations of femur or tibia from 3° varus to 3° valgus) was less than that (57.8%,37/64) in the dense area (set of all combinations except sparse area),and the difference was significant (x2=29.61,P< 0.001).Conclusion It is suggested that the position of the femoral component and the tibial component in fixed medial unicom partmental arthroplasty should not exceed 3° varus or valgus in patients with standard lower limb alignment.
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Revision total hip arthroplasty is becoming more common due to an increasing number of primary total hip arthroplasty procedures being performed annually. Chronic pelvic discontinuity is an important and difficult complication after primary total hip arthroplasty. It is estimated that chronic pelvic discontinuity account for 1%-5% of all acetabular revisions. Pelvic discontinuity occurs mostly in female patients or patients with a history of prior pelvic radiation or rheumatoid arthritis. There are three following crucial factors in regards to achieving satisfied outcomes in treating pelvic discontinuity, the amount of bone stock remaining, biologic in-growth potential and the healing potential of the discontinuity. Treatment approaches include cage reconstruction with bulk acetabular allograft, custom triflange acetabular component, a cup-cage construct, jumbo acetabular cup with porous metal augments, and acetabular distraction with a porous tantalum shell with or without modular porous augments. The present course reported the classification, evaluation, reconstruction options and outcomes of chronic pelvic discontinuity.
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Periprosthetic femoral fracture (PFF) is one of severe complications after total hip arthroplasty (THA). As the number of patients receiving THA increased recently, the incidence of PFFs also increased dramatically. There are a number of risk factors for PFFs, such as age, sex, falling and prosthesis loosening. The Vancouver classification system is the most commonly used classification method for PFFs. According to the fracture location, PFFs can be divided into type A intertrochanteric fracture, type B fracture around the stem and type C fracture beyond the stem. The Vancouver type B PFF is further subdivided into type B1 with a well?fixed prosthesis, type B2 with a loose prosthesis but with adequate bone stock, and type B3 with a loose prosthesis and poor proximal bone stock simultaneously. Currently, there are some controversies in treating PFFs, mainly including whether the stem is fixed or not, whether the prosthesis needs to be revised, the selection of the stem, the reconstruction of bone defects, and the methods of fracture fixation. We searched literatures related to PFFs after THA. The incidence, risk factors, classification meth?ods, treatment principles and strategies of PFFs were summarized in the present study. Based on our long?term clinical experience, we evaluated the advantages and disadvantages of each treatment method and provided considerations for the clinical research and selection in treating PFFs.
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Periprosthetic femoral fracture (PFF) is one of severe complications after total hip arthroplasty (THA). As the number of patients receiving THA increased recently, the incidence of PFFs also increased dramatically. There are a number of risk factors for PFFs, such as age, sex, falling and prosthesis loosening. The Vancouver classification system is the most commonly used classification method for PFFs. According to the fracture location, PFFs can be divided into type A intertrochanteric fracture, type B fracture around the stem and type C fracture beyond the stem. The Vancouver type B PFF is further subdivided into type B1 with a well-fixed prosthesis, type B2 with a loose prosthesis but with adequate bone stock, and type B3 with a loose prosthesis and poor proximal bone stock simultaneously. Currently, there are some controversies in treating PFFs, mainly including whether the stem is fixed or not, whether the prosthesis needs to be revised, the selection of the stem, the reconstruction of bone defects, and the methods of fracture fixation. We searched literatures related to PFFs after THA. The incidence, risk factors, classification methods, treatment principles and strategies of PFFs were summarized in the present study. Based on our long-term clinical experience, we evaluated the advantages and disadvantages of each treatment method and provided considerations for the clinical research and selection in treating PFFs.
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Objective To investigate the results of malformation correction of femoral medullary cavity in hip revision for implant loosening.Methods From January 2010 to December 2016,24 patients (24 hips) were received hip revision arthroplasty using femoral medullary cavity correction technique.Nineteen patients (19 hips) were followed up.Ten patients were male and 9 female with mean age of 69.1 years (range 44-84).The followings are the reasons for revision:15 patients for osteolysis with implant loosening,4 for periprosthetic infection,bone cement implant and stage two revision.Fourteen patients received bone cement implants and 5 received uncemented implants for primary arthroplasty.During revision,13 patients underwent femoral bone cortical windowing and 6 received extended trochanteric osteotomy technique to exposure medullary cavity,grinding sclerotic bone and filling bone defect,correcting cavity to normal morphology and implant anatomic revision stem.The hip function was evaluated with Harris score.Peri-operation complications were also collected.Implant position,fixation condition and implant loosening were evaluated from the supine anteroposterior radiograph of the pelvic and a lateral hip radiograph.Results The mean follow up duration was 58 months (range 17-82).The mean Harris score improved significantly from 41.52±10.94 (range 17-64) preoperatively to 91.63±6.70 (range 72-99) postoperatively.Mild limp occurred in 2 patients (11%,2/19) and intermittent hip pain occurred in 1 patient (5%,1/19).Peri-prosthetic fracture occurred in 1 patient and was treated with double stranded wire fixation.No deep venous thrombosis,dislocation and infection occurred.No revision was performed.For bone cortical windowing patients,the length of the cortical windows varied from 3.0 to 9.0 cm (mean 4.78±1.84),the width ranged from 1.0-3.0 cm (mean 1.82± 0.50).For extended trochanteric osteotomy patient,the length of the osteotomy varied form 12.0-20.0 cm (mean 16.00±3.37),the width ranged from 2.5 to 3.0 cm (mean 2.75±0.29).All the revision stems were in neutral position without varus or valgus.All the osteotomy sites were bone heal and fracture lines were disappeared.Conclusion In order to restore the normal bone cavity morphology and femoral alignment,correction bone cavity technique is required in patients receiving hip revision with femoral cavity malformation and anatomy alignment abnormal.This technique can ensure neutral position of revision stem without peri-prosthetic fracture.
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Objective To compare faster rehabilitation of different surgical approaches in total hip arthroplasty (THA)patients using a direct anterior approach or posterolateral approach.Methods Sixty-eight patients (35 in direct anterior THA and 33 in posterolateral THA) from September 2015 to March 2016 were recruited in the present study.The incision length,operation duration,intraoperative blood loss,serum creatinekinase (CK),C-reactive protein (CRP),erythrocyte sedimentation rate (ESR),interleukin-6 (IL-6) and visual analogue scale (VAS) pain score were compared between two groups respectively.The Harris hip score,the University of California at Los Angeles (UCLA) pain,walking,and activity scores,postoperative hospital length of stays,gait analysis,component placement and complications were also compared.Results The mean incision length,operation duration,intraoperative blood loss were 11.23±0.97 cm,73.77±9.20 min and 157.15±35.83 ml in the DAA group respectively,while those in PLA group were 15.16±1.12 cm,64.12±13.31 min and 126.97±45.45 ml.The mean incision length of the DAA group were significantly less than that of the PLA group.The DAA group underwent longer operation time that associated with more intraoperative blood loss.The levels of CK and inflammation markers were increased in the PLA group compared with those in the DAA group.The VAS pain score was less in the DAA group than the PLA group within postoperative 72 hours.Functional recovery in the DAA group was faster than that in the PLA group based on the Harris hip score,UCLA scores,and gait analysis up to 3 months.There was no difference in these outcomes between the groups beyond 6 months.The average postoperative hospital length of stay was 2.95±0.24 days and 3.35±0.51 days for the DAA group and PLA group respectively.The patients in DAA group required less postoperative hospital length of stays.The angle of acetabular cup anteversion in the DAA group (16.4°±2.3°) was lesser than that in the PLA group (20.4°±2.8°).There was one intraoperative nondisplaced greater trochanter fracture in the DAA group,whereas no intraoperative complications were occurred in the PLA group.Conclusion The present study showed that using direct anterior approach in THA provided significant benefits for patients in terms of muscle damage,VAS score,hospital length of stays and functional recovery in the early stage postoperatively compared to using posterolateral approach.
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Objective To investigate the results of malformation correction of femoral medullary cavity in hip revision for implant loosening.Methods From January 2010 to December 2016,24 patients (24 hips) were received hip revision arthroplasty using femoral medullary cavity correction technique.Nineteen patients (19 hips) were followed up.Ten patients were male and 9 female with mean age of 69.1 years (range 44-84).The followings are the reasons for revision:15 patients for osteolysis with implant loosening,4 for periprosthetic infection,bone cement implant and stage two revision.Fourteen patients received bone cement implants and 5 received uncemented implants for primary arthroplasty.During revision,13 patients underwent femoral bone cortical windowing and 6 received extended trochanteric osteotomy technique to exposure medullary cavity,grinding sclerotic bone and filling bone defect,correcting cavity to normal morphology and implant anatomic revision stem.The hip function was evaluated with Harris score.Peri-operation complications were also collected.Implant position,fixation condition and implant loosening were evaluated from the supine anteroposterior radiograph of the pelvic and a lateral hip radiograph.Results The mean follow up duration was 58 months (range 17-82).The mean Harris score improved significantly from 41.52±10.94 (range 17-64) preoperatively to 91.63±6.70 (range 72-99) postoperatively.Mild limp occurred in 2 patients (11%,2/19) and intermittent hip pain occurred in 1 patient (5%,1/19).Peri-prosthetic fracture occurred in 1 patient and was treated with double stranded wire fixation.No deep venous thrombosis,dislocation and infection occurred.No revision was performed.For bone cortical windowing patients,the length of the cortical windows varied from 3.0 to 9.0 cm (mean 4.78±1.84),the width ranged from 1.0-3.0 cm (mean 1.82± 0.50).For extended trochanteric osteotomy patient,the length of the osteotomy varied form 12.0-20.0 cm (mean 16.00±3.37),the width ranged from 2.5 to 3.0 cm (mean 2.75±0.29).All the revision stems were in neutral position without varus or valgus.All the osteotomy sites were bone heal and fracture lines were disappeared.Conclusion In order to restore the normal bone cavity morphology and femoral alignment,correction bone cavity technique is required in patients receiving hip revision with femoral cavity malformation and anatomy alignment abnormal.This technique can ensure neutral position of revision stem without peri-prosthetic fracture.
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Objective To compare faster rehabilitation of different surgical approaches in total hip arthroplasty (THA)patients using a direct anterior approach or posterolateral approach.Methods Sixty-eight patients (35 in direct anterior THA and 33 in posterolateral THA) from September 2015 to March 2016 were recruited in the present study.The incision length,operation duration,intraoperative blood loss,serum creatinekinase (CK),C-reactive protein (CRP),erythrocyte sedimentation rate (ESR),interleukin-6 (IL-6) and visual analogue scale (VAS) pain score were compared between two groups respectively.The Harris hip score,the University of California at Los Angeles (UCLA) pain,walking,and activity scores,postoperative hospital length of stays,gait analysis,component placement and complications were also compared.Results The mean incision length,operation duration,intraoperative blood loss were 11.23±0.97 cm,73.77±9.20 min and 157.15±35.83 ml in the DAA group respectively,while those in PLA group were 15.16±1.12 cm,64.12±13.31 min and 126.97±45.45 ml.The mean incision length of the DAA group were significantly less than that of the PLA group.The DAA group underwent longer operation time that associated with more intraoperative blood loss.The levels of CK and inflammation markers were increased in the PLA group compared with those in the DAA group.The VAS pain score was less in the DAA group than the PLA group within postoperative 72 hours.Functional recovery in the DAA group was faster than that in the PLA group based on the Harris hip score,UCLA scores,and gait analysis up to 3 months.There was no difference in these outcomes between the groups beyond 6 months.The average postoperative hospital length of stay was 2.95±0.24 days and 3.35±0.51 days for the DAA group and PLA group respectively.The patients in DAA group required less postoperative hospital length of stays.The angle of acetabular cup anteversion in the DAA group (16.4°±2.3°) was lesser than that in the PLA group (20.4°±2.8°).There was one intraoperative nondisplaced greater trochanter fracture in the DAA group,whereas no intraoperative complications were occurred in the PLA group.Conclusion The present study showed that using direct anterior approach in THA provided significant benefits for patients in terms of muscle damage,VAS score,hospital length of stays and functional recovery in the early stage postoperatively compared to using posterolateral approach.
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Objective:To evaluate the result of operation and gait analysis at the early stage after direct anterior approach (DAA) in total hip arthroplasty (THA).Methods: In this study,20 patients who suffered from necrosis of femoral head or developmental dysplasia of the hip were scheduled to undergo THA.The basic information and visual analogue scale (VAS) score,Harris score before and after surgery were recorded.All of the patients finished the gait analysis before the surgery and 6 weeks and 12 weeks after the surgery,the data were compared with those of normal adult people.Results: Their hospital stay after the operation was 3.3 d,the VAS score after the operation was no more than 4 points,the positions of prosthesis were satisfactory,and there was no dislocation.The gait analysis results contained step speed,stride,the range of motion (ROM) of hip and knee.The step speed before the surgery (preoperation,Pre) was 0.64 m/s,6 weeks after the surgery (6W) was 0.77 m/s,12 weeks after the surgery (12W) was 1.07 m/s,and the control group was 1.19 m/s.The stride at Pre,6W,12W,and control group were 43.15 steps/min,51.42 steps/min,55.52 steps/min,and 57.15 steps/min,respectively.The ROM of hip joint at Pre,6W,12W,and control group were 31.00°,39.62°,40.40°,and 45.67°,respectively.The ROM of knee joint at Pre,6W,12W,and control group were 50.52°,59.28°,67.29°,and 70.42°,respectively.The results of the gait analysis showed that the gait recovery after the direct anterior total hip arthroplasty was very fast and at the 12th week after surgery the gait of the patients was close to the normal adult people.Conclusion: The direct anterior approach is one of the choosable approach of the THA,and this kind of surgery has a better recovery of gait after the operation,and at the end of 12 weeks after the surgery the gait is very close to the normal adult people.But we also need more studies to prove this conclusion.
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Objective To explore the effects of multiple intravenous tranexamic acid (Ⅳ-TXA) administrations after total knee arthroplasty (TKA) on fibrinolytic activity and inflammatory response in an enhanced recovery after surgery (ERAS) program and to assess the efficacy and safety of Ⅳ-TXA.Methods One hundred and forty-one severe knee osteoarthritis patients following primary unilateral TKA from January 2016 to April 2017 were investigated retrospectively.The patients were divided into following three groups based on the dosage of Ⅳ-TXA after surgery:40 patients received ≤3 g Ⅳ-TXA after surgery (group T1),50 patients received 4 g (group T2) and the other 51 patients received ≥5 g Ⅳ-TXA (group T3).The total blood loss (TBL),hidden blood loss (HBL),transfusion rate,maximum hemoglobin (Hb) drop,the incidence of intramuscular venous thrombosis,deep vein thrombosis (DVT) and pulmonary embolism (PE),fibrinolysis parameters [fibrin(-ogeu) degradation products (FDP),D-dimer],and inflammation markers [C-reactive protein (CRP),interleukin-6 (IL-6)] during perioperative period were evaluated.In addition,correlation analyses between the dosage of Ⅳ-TXA and fibrinolysis parameters and inflammation markers were conducted.Results The mean TBL,HBL and maximum Hb drop in group T2 (537.16±270.43 ml,431.36±271.99 ml,19.68± 10.68 g/L) and T3 (541.31±290.00 ml,439.94±290.71 ml,20.24±8.48 g/L) were lower than those in group T1 (748.22±394.34 ml,P=0.012,0.013;636.47±388.14 ml,P=0.011,0.015;25.88± 11.77 g/L,P=0.005,0.010,respectively).No patient needed transfusion in all groups.There was no statistically difference in the incidence of intramuscular venous thrombosis of lower limbs among three groups (P> 0.05).No episode of DVT or PE occurred in any group in two weeks after surgery.There were negative correlation between the dosage of Ⅳ-TXA and FDP at postoperative day 1 and day 3 (r=-0.191,P=0.025;r=-0.291,P=0.001) and D-dimer on postoperative day 3 (r=-0.176,P=0.048).Moreover,the CRP (r=-0.184,P=0.036) and IL-6 (r=-0.269,P=0.002) level in serum on postoperatire day 1 also showed a negative relationship with the dosage of Ⅳ-TXA after surgery.Conclusion The multiple Ⅳ-TXA (≥4 g) after surgery can further reduce the TBL,HBL and maximum Hb drop following primary TKA in ERAS program without increasing the risk of thrombotic events.Most importantly,the effect of anti-fibrinolysis will be enhanced and may have an anti-inflammatory effect with the dosage of Ⅳ-TXA increased.
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Objective To investigate biomechanical effects of different joint line height on unicompartmental knee arthroplasty (UKA) and to provide biomechanical evidence for surgical decision during UKA using finite element analysis (FEA).Methods On the basis of knee joint CT data from a healthy volunteer (male,30 years old,165 cm and 60 kg) and UKA prosthesis 3D scanned data,the 3D models of normal knee and UKA were constructed.Subject-specific finite element models with inhomogeneous material property assignment were constructed for normal knee and UKA with 3 different height of joint line (-3 mm,0 mm and +3 mm).Starting from the tibial articular surface,5 sections were extracted with 2 mm interval.30 nodes were selected in medial and lateral area,respectively on each section.The mean stress value of nodes was defined as the stress level of subchondral bone.Results Mean values of stress on polyethylene upper surface of 0,-3 and+3 mm joint line position were 14.84,26.81and 20.86 MPa,and the difference was statistical significant (t0vs-3=4.896,P0vs-3=0.000;t0vs+3=3.455,P0v+3=0.008;t-3vs+3=2.579,P-3vs+3=0.020).Mean values of stress on tibial prosthesis upper surface of 0,-3 and +3 mm joint line position were 29.69,50.49 and 39.99MPa,respectively,and the difference was statistical significant(t0vs-3=5.675,P0vs-3=0.000;t0vs+3=4.755,P0v+3=0.001;t-3vs+3=4.783,P-3vs+3=0.000).When joint line was in 0 mm height,stress level of subchondral bone was similar to that of normal knee.When joint line was in-3 mm height,significantly increased stress was found on polyethylene (increased 81%) and tibial component (increased 70%) surface compared with that of 0 mm height,while stress on trabecular bone under lateral tibial articular surface also increased by 8.7%.When joint line was in +3 mm height,increased stress on polyethylene (increased 41%) and tibial component (increased by 35%) surface were less than that of-3 mm height.Stress on trabecular bone under lateral articular surface decreased by 55.6% compared with 0 mm height.Conclusion During UKA,ensuring a normal height of joint line is benefit to keep the stress path of the medial and lateral tibia similar with normal knee and decrease the risk of premature polyethylene wear,tibial component subsidence and periprosthetic fracture.
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<p><b>OBJECTIVE</b>To investigate the effectiveness and safety of post-operative retransfusion drain(PRD) after total hip arthroplasty.</p><p><b>METHODS</b>A systematic literature review based on PubMed, EMBase, the Cochrane Library, China Biology Medicine disc, CNKI, VIP and WanFang Database in any language regarding PRD following total hip arthroplasty was performed.The data was evaluated using modified Jadad score and then analyzed using RevMan 5.2.</p><p><b>RESULTS</b>Nine randomized controlled trials totaling 1 824 patients, 913 patients in PRD group and 911 in control group, were eligible for data extraction and Meta-analysis.The results indicated that the use of PRD could reduce the requirement of allogeneic blood transfusion when compared with ordinary vacuum drainage (RR=0.61, 95% CI= 0.47-0.79), but the benefit was not found when compared with no drainage group(RR=1.07, 95% CI=0.67-1.71). And the postoperative hemoglobin level was higher in PRD group(MD=0.14, 95% CI=0.01-0.27, P=0.04). No significant difference was identified regarding transfusion index, length of hospital stay, the incidence of febrile reaction and wound-related complications.</p><p><b>CONCLUSIONS</b>PRD in reducing requirement of blood transfusion following THA is effective and safe when compared with ordinary vacuum drainage, but the benefit is not found when compared with no drainage.And more robust evidence is needed to confirm this result.</p>
Subject(s)
Humans , Arthroplasty, Replacement, Hip , Blood Transfusion , China , Drainage , Methods , Length of Stay , Postoperative Period , Randomized Controlled Trials as TopicABSTRACT
Objective To evaluate mid?term clinical outcomes associated with total hip arthroplasty using metal?on?met?al prosthesis with large diameter femoral head. Methods From March 2007 to December 2009, 153 patients (177 hips) with ad?vanced hip diseases undergoing large diameter femoral head metal?on?metal total hip arthroplasty in our hospital were retrospec?tively analyzed in this study. Clinical physical examination and radiographic examination were used to evaluate hip function and the incidence of complications (implant loosening and inflammatory pseudotumor);ICP?MS method was used to determine serum cobalt ion and chromium ion levels and compare with normal values;revision was set as the prosthesis endpoint to evaluate the five year survival rate of implant. Results A total of 145 patients (169 hips) were followed up for average 72.4 months (67-80 months), the follow?up rate was 94.8% (145/153). For the involved patients, 85 were male (104 hips), 60 were female (65 hips);age 20-78 years old, average 49.3±12.6 years old. All patients received ASRTM?XL large femoral head metal?on?metal to?tal hip arthroplasty operation. At the end of follow?up, the average Harris hip score improved from 44.2±12.6 points preopera?tively to 91.5±5.7 points. A total of 8 patients received revision, 3 for acetabular implant spinout?out and 5 for hip inflammato?ry pseudotumor. The prosthetic survival rate 5 years after operation was 95.3% (161/169) for revision. Serum cobalt (2.89 μg/L) and chromium (3.31 μg/L) ion levels were significantly increased compared with normal value (<0.5 μg/L). Conclusion For the fixation and friction interface disadvantages, acetabular implant spinout?out and inflammatory pseudotumor might occur for patient receiving large femoral head metal?on?metal THA. The mid?term prosthetic survival rate was also low, with metal ion levels increased significantly. For primary THA, large femoral head metal?on?metal prosthesis cannot be the first choice.
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Objective To investigate the expression of miRNA-140 in chondrocytes and synovial fluid of osteoarthritis (OA) patients, and explore the relationship between the miRNA-140 expression and OA severity.Methods This study enrolled 30 OA patients who underwent total knee arthroplasty for chondrocytes sampling and 30 OA patients who underwent intra-articular injection for synovial fluid sampling. All OA patients were grouped into mild [Kellgren and Lawrence (KL) grade 1-2], moderate (KL grade 3) and severe (KL grade 4), with 10 in each subgroups for each sampling purposes. 7 non-OA patients and 10 patients with knee injury were collected for cartilage and synovial fluid sampling respectively as control groups. Chondrocytes were isolated from the cartilage tissue and cultured in vitro. Quantitative real time PCR for miRNA-140 in chondrocytes and synovial fluid were performed, and the U6 snRNA was used as internal control. The expression difference of miRNA-140 among groups and correlation between the expression and the KL grade of OA were analysed using one-way ANOVA and Spearman test respectively. Results The expression of miRNA-140 in chondrocytes of knees in OA patients was reduced than that in normal knees, and the between-group difference was statistically significant (F=305.464, P<0.001). miRNA-140 could be detected in synovial fluid of both normal knees and OA knees, its relative expression level was reduced in synovial fluid of OA group compared with normal group, and the between-group difference was statistically significant as well (F=314.245, P<0.001). The relative expression level of miRNA-140 in both chondrocytes and synovial fluid were negatively correlated with the KL grade of OA(r=-0.969, P<0.001; r=-0.970, P<0.001). Conclusion miRNA-140 could be detected in chondrocytes and synovial fluid of OA patients, and its expression was negatively correlated with the severity of OA.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Cells, Cultured , Chondrocytes , Metabolism , Knee Joint , Metabolism , MicroRNAs , Osteoarthritis, Knee , Metabolism , Real-Time Polymerase Chain Reaction , Synovial Fluid , MetabolismABSTRACT
The basic stress pathway above the acetabular dome is important for the maintenance of implant stability in acetabular reconstruction of total hip arthroplasty (THA). The purpose of this study was to describe the basic stress pathway to provide evidence for clinical acetabular reconstruction guidance of THA. A subject-specific finite element (FE) model was developed from CT data to generate 3 normal hip models and a convergence study was conducted to determine the number of pelvic trabecular bone material properties using 5 material assignment plans. In addition, in the range of 0 to 20 mm above the acetabular dome, the models were sectioned and the stress pathway was defined as two parts, i.e., 3D, trabecular bone stress distribution and quantified cortical bone stress level. The results showed that using 100 materials to define the material property of pelvic trabecular bone could assure both the accuracy and efficiency of the FE model. Under the same body weight condition, the 3D trabecular bone stress distributions above the acetabular dome were consistent, and especially the quantified cortical bone stress levels were all above 20 MPa and showed no statistically significant difference (P>0.05). Therefore, defining the basic stress pathway above the acetabular dome under certain body weight condition contributes to design accurate preoperative plan for acetabular reconstruction, thus helping restore the normal hip biomechanics and preserve the stability of the implants.
Subject(s)
Humans , Acetabulum , Arthroplasty, Replacement, Hip , Biomechanical Phenomena , Finite Element Analysis , Hip Prosthesis , Imaging, Three-Dimensional , Stress, Mechanical , Tomography, X-Ray ComputedABSTRACT
Objective To investigate the efficacy and safety of tranexamic acid on bleeding in rheumatoid arthritis (RA) patients undergoing total hip arthroplasty (THA). Methods A retrospective study was performed in 197 RA patients (Steinbrock?er III-IV) following primary unilateral THA from June 2012 to June 2014. The patients were divided to three groups based on the regimen of tranexamic acid:68 patients received a single intravenous dosage of 15 mg/kg tranexamic acid 20 min prior to opera?tion (single dose group);74 patients received an intravenous dosage of 15 mg/kg preoperatively and a second dosage of 10 mg/kg 3 hours postoperatively (repeated dose group);the other 55 patients didn't receive tranexamic acid (control group). The primary out?comes were total blood loss, transfusion rate, the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE). The sec?ondary outcomes were postoperative drainage, hemoglobin (Hb) drop on third day postoperatively and other wound related compli?cations. Results There was less total blood loss (816.80 ± 245.09 ml vs 975.15 ± 216.33 ml vs 1 295.68 ± 263.85 ml), drainage (221.60 ± 70.05 ml vs 337.20 ± 113.10 ml vs 479.74 ± 120.66 ml), transfusion requirement (5.41%vs 10.29%vs 25.45%) and Hb drop (2.71±0.74 g/dl vs 3.18±0.62 g/dl vs 3.83±0.70 g/dl) in experimental group when compared with control group. And the effect was better in repeated dose group, with less total blood loss (816.80 ± 245.09 ml), less transfusion requirement (5.41%) and less postoperative drainage (221.60±70.05 ml). No episode of DVT or PE occurred in either group. There were 8 wound complications in single dose group, 6 in repeated group, and 8 in control group, and there were no statistically difference. Conclusion Intrave?nous administration of tranexamic acid was effective and safe on decreasing blood loss and transfusion requirement in RA patients following THA. Compared with a single dosage of tranexamic acid preoperatively, a second dosage of tranexamic acid 3 hours post?operatively was recommended.
ABSTRACT
Objective To determine medium-term curative effect of extensively coated non-modular femoral stems in twostage infection revision after joint replacement.Methods We retrospectively analyzed 33 patients (33 hips) who had a two-stage infection revision after total hip replacement arthroplasty from March 2005 to December 2006.Among of them,there were 20 men (20 hips) and 13 women (13 hips).Their mean age was 66.1±7.2 years with a range from 52 to 80.The two-stage revision protocol consisted of joint prosthesis taken out in the first stage,thorough debridement,hand-molded antibiotic bone cement spacer,and two-stage joint revision after anti-infective therapy.Anti-infective therapy included intravenous antimicrobial therapy for 4 weeks and oral antibiotics for 6 weeks.Harris hip score (HHS) was used to evaluate functions of hip joint.X-ray films were used to perform clinical and radiological evaluations of prosthesis stability,displacement and looseness.Reinfection criteria were the same as the criteria used to diagnose the joint infection.Results Follow-up visit was carried out for all patients for 5-9 years (6.1±1.7 years on the average).No infection or prosthesis looseness happened after two-stage revision.Microculture of samples taken during two-stage revision or pathological examination was negative.Harris hip joint score rose to 89.1 ±8.5 in the last follow-up visit from preoperative 42.3±6.5.30 patients achieved stable bone ingrowths and the remaining three had stable fibrous ingrowths.Impacted bone graft at acetabulum side for 11 patients and all impacted bone graft in marrow cavity were fused well with the host bones.Allogeneic cortical bone plate grafts were used in 10 hips on the femoral side.Nine of these cortical bone plates fused with the host bones after postoperative 1 year,whereas one fused after 2 years.Conclusion Using extensively coated non-modular femoral stems combined with intramedullary allograft in two-stage revision for treating infection can achieve satisfactory medium-term survival rate of prosthesis and infection clearance rate.